Technical Field
This present disclosure relates generally to the lubrication of a gear. More particularly, the disclosure relates to the use of an aperture in a gear that allows lubricant to be delivered from a cavity within the gear to a toothed portion of the gear.
Description of Related Art
Aircraft drivetrains can include various components that produce and transfer power. For example, engines and gearboxes are common components. Such components generate heat and require lubrication. Excessive levels of heat can cause premature failure and create safety risks. Proper lubrication serves to reduce hard contact between moving components and reduce heat production.
Typically, aircraft use a variety of primary lubrication systems to provide wear protection and heat transfer within components. Under normal operating conditions, primary lubrication systems provide proper lubrication and heat removal. However, in cases of emergency, primary lubrication systems can fail resulting in excessive wear and failure of components, such as a gearbox or transmission.
Aircraft are generally required to maintain manageable flight operations for selected durations of time if the primary lubrication system fails (zero pressure). One method used to satisfy the requirements of manageable flight during a lubrication system failure is to increase the amount of lubricant reserves with resulting increase in the weight of the lubricant. Another method is to use a secondary lubrication system to operate when the primary lubrication system fails. Although not commonly used, secondary systems typically provide only sufficient lubricant to lubricate moving parts but can fail to adequately remove heat. Both methods increase the overall weight of the aircraft and can fail to sufficiently prevent heat generation. Therefore, an improved method of lubricating the gears of an aircraft gearbox during a loss of lubrication event is desired.